Exemplary embodiments of the invention relate to the art of turbomachine inlet filter systems and, more particularly, to a drain for a turbomachine inlet filter system.
Modern turbomachines include a number of rotating components that operate within tight tolerances. Foreign matter ingested into an intake of the turbomachine can cause damage, excessive wear, or even catastrophic failure. Thus, turbomachines are provided with various systems that function to remove foreign particulate from intake airstreams. In general, geographical constraints dictate particulate removal levels for the turbomachines. Turbomachines operating in a relatively dry, clean environment require a lower level of particulate removal as compared to turbomachines operating in harsh environments such as, off-shore oil rigs. In addition to removing particulate, turbomachines are provided with filtration systems that remove moisture from intake airstreams. The liquid can carry chemicals such as salts, acids and the like which could damage internal turbomachine components. Once captured, the moisture is passed to a drain and guided away from the turbomachine.
Existing moisture systems employ a manometric drain that includes a drain box. The drain box is periodically filled with fluid (water) that forms a trap preventing a flow of unfiltered air from bypassing a filtration system and entering the turbomachine intake. More specifically, when in operation, a high velocity airflow enters the turbomachine. The high velocity airflow passes across the drain creating a pressure differential that can pull in additional, unfiltered, air thereby defeating the purpose of the filtration system. In order to prevent the backflow of air, the drain box is partially filled with water to form a trap. However, over time, the water in the drain box dissipates and requires replenishment. Unfortunately, maintenance schedules are not always strictly followed and the water in the drain box is often not replenished in time. In such situations, and despite a large capital investment in filtration systems, unfiltered air enters the turbomachine.